Figure: Rie (custom figure based on https://www.daz3d.com/rhonwen-hd-for-genesis-8-female )
Outfit: https://www.daz3d.com/realfit-string-bikini
Environment: https://www.daz3d.com/ultrahd-iray-hdri-with-dof-pines-beach

Rendering result is post-processed with photoshop.